How do I force the flash to go off in manual mode? Help!!!

algmiyazaki

Senior Member
I need some help with something that has been causing me much frustration.

Lately I've been trying to force my flash to go off, no matter what, when I'm taking outdoor macro photos with my D5100. However, I've tried everything and can't get it to work. The only time it will go off is if the lighting is REALLY dark (nearly pitch black), which is extremely annoying. I want it to go off for taking insect photos but it just won't, even on a cloudy day or at dusk or dawn. If I cover the area up with my shadow to make it exceedingly dark, then it goes off.

I'm using manual mode. I have the flash open and set to fill flash. Tried P, A, and S. Never use anything else so didn't try it.

Is there no way to force it to go off? Am I going to have to buy external? I hate having to crank up my ISO to 1600+, too much noise.

Thanks.
 

wev

Senior Member
Contributor
Try pushing the fstop way high. I shot a hummingbird that way today -- iso 100, 1/200, f22 and the flash set to manual 1/2. Flash fired and I got the shot.
 

algmiyazaki

Senior Member
Hm, I'll try a higher f-stop next time. I was using f7.1, I believe.

I'll also try and see if the subject distance affects it. I'm using the 40mm since I can't afford 105mm so I was within 1 foot of the subject each time. Do you know if that applies with auto focus, manual focus or both?

Thanks for the replies so far!
 

wev

Senior Member
Contributor
I shoot a 5200 and have no issues with a short focal distance and the flash firing in manual mode. Perhaps it is a function of Macro mode?
 

aroy

Senior Member
I never tested the flash at short distance, but with "G" lense the camera does not shoot if the distance is less than the minimum distance for the lense.

The D3300 manual says that the in built flash has a minimum range of 0.6m (2 feet) and cannot be used in the macro range of the zoom lense. On page 295 the manual has a list of lenses where the flash may vignett. Check your manual for compatible lenses.
 

WayneF

Senior Member
My D800 and D300 manuals both also say built in flash "cannot be used" at macro distances, less than 2 feet, but it works anyway on both of them. It does flash at six inches. I think "cannot be used" only means ought not be used, accuracy could be suspect. Plus the danger of the lens blocking the flash..

I cannot speak for the D7100 (but really doubt it is different). It would seem this is just a warning about accuracy, not a statement about disabling it.

Normally, the flash will always fire in A, S, P, or M modes, in any situation, if the flash door is open (and if the internal flash is recycled to Ready... Ready indicator is lighted).
 

algmiyazaki

Senior Member
Hm, mine definitely does not go off all the time in manual. I will mess around with it the next time I am out shooting macro and see if I can find out what is preventing it from triggering. I'll post my results. (Hopefully it's not some sort of defect?)

Thanks!
 

Sandpatch

Senior Member
Furthering algmiyazaki's question, how do you force the flash to fire in non-macro photography? There are times when I have a shot in shade with bright light behind and so would very much like to force the flash to fire, but it won't. I've never been able to figure this out. Thank you.
 

algmiyazaki

Senior Member
I've just given up on figuring this out. I don't think even Nikon knows the answer. I've tried everything and it seems to be completely random. Sometimes it'll go off in broad daylight and sometimes it won't go off even after the sun has set. It never matters if I change the aperture or if I'm shooting in macro.

For example, one bright afternoon I was shooting flowers that were in the shade and it was going off no problem (macro). The next day I was up shooting flowers again, 45 minutes before sunrise in considerably darker conditions (much darker than the shaded area) and it wouldn't go off. Same lens, same fixed focal length, tried all sorts of settings. When this happens the only way I can force it to go off is put my hand in front of the lens to the point where the image is extremely dark (pitch black). Obviously this won't work as I don't want pictures of my hand!
 

Eyelight

Senior Member
Different settings control the flash at different times in different ways. Depends on all the variables.

If you post the lens you are using and the settings used when it works and when it does not, someone may be able to help figure it out.
 

aroy

Senior Member
In my D3300 (and I am sure it will be same in your camera), there is a menu item - "Flash cntrl for built-in-flash". Enter the menu and select Manual. Under that you have different power setting from full to 1/32. That setting with flash popped up and at Aperture priority, with Auto ISO switched off fires the flash every time. That is what I do with AIS lenses. You have to control the flash intensity manually, but a few trials will get you there.

Setting the flash intensity manually is not much of a problem.
. The guide number is the distance the flash will illuminate at F1.0 and ISO 100. As the flash will fire at more than 1/5000 second, the speed should be set at the maximum flash synchronization speed (1/200 in case of D3300)
. From the guide number and the distance of the object you can get the maximum distance.
. From your object distance you can calculate the intensity.

Flash Photography - Understanding Guide Numbers
 

algmiyazaki

Senior Member
Thank you for your replies. I wasn't aware of that setting but it hasn't solved the issue.

I did extensive testing today while out hiking. No settings on the camera have any effect on whether the flash triggers or not. Neither does the type of lens, the focal length, or whether or not it is macro. It appears to be related to lighting but my camera just isn't very good at detecting it. I noticed three things that affected whether or not it fired:

-Lighting (seems weird, as sometimes it triggers in bright light)
-Perspective (probably due to changes in lighting)
-Distance from subject (also could be caused by lighting detection)

I found patterns in its behavior while shooting damselflies. For example, the damselfly was on a rock. My focal length was set at 90mm (Tamron) or 40mm (Nikon). Changed lenses, f-stops, shutter speeds, menu settings, etc. and none of that determined if the flash fired or not.

What DID happen was this: if I was shooting at a fixed distance, say 3 feet from the subject, and I changed this distance, it sometimes would stop firing (both getting closer AND farther away). When I went back to the distance I was at before, it would fire successfully.

Another thing that happened: if I changed my perspective it would cease to fire. I found it fired the most if there was a solid, flat background, such as a rock or ground. If I shot directly above the rock it would go off BUT if I kneeled down so that I was shooting the rock from a side angle it wouldn't fire anymore. It wouldn't fire for flies that were sitting on branches, grass blades, flowers, etc.

I just wish there were a way to get it to fire no matter what. Is my only option to buy external flash? (Will I be able to force that to go off 100% or will it still tie in to the camera? I've never used an external before.)
 

algmiyazaki

Senior Member
I should add that in every case in which that flash wasn't firing, if I put my hand in front of the lens it successfully fired. It's definitely about the amount of light but I just wish there was a way to ignore that.
 

aroy

Senior Member
Are you using "Matrix" metering? If so, try "Spot" or "Center Weighed", that may help. Another thing is that the lens/camera combination may not be detecting the distance properly. For TTL to work the distance has to be reported by the lens. I have 50mm F1.8, non D, so the flash has to be compensated for every distance, but I have never had the flash not firing.

By the way do you keep your flash "popped up" or assume that the flash will pop up when needed. In my case with the flash popped up it fires every time - under Aperture Priority setting. If you are using the program modes, then the camera does the thinking for you.
 

algmiyazaki

Senior Member
Hm I was using matrix the whole time. I'll try spot and see if that will help. I always have the flash popped up.

It's in manual mode that it's not firing. I haven't tried aperture priority so I'll give that a shot, too. Thanks!
 

WayneF

Senior Member
I just wish there were a way to get it to fire no matter what. Is my only option to buy external flash? (Will I be able to force that to go off 100% or will it still tie in to the camera? I've never used an external before.)

I think "get it to fire" means "to pop open automatically and then fire". I think you must be using Auto camera mode. In camera Auto mode, the camera system decides (depending on ambient light) when it needs to pop open and fire.

If you instead use one of camera modes A, S, P, or M, then the internal flash will always fire if you open its door manually, and it will never open automatically if you close its door. But Auto mode means that it decides.

I would suggest camera A mode to start. A mode means you set f/stop yourself, wider values like f/4 or f/5.6 will have much move effective flash power than like f/8 or f/11, which could demand more power than the little internal flash can deliver, in some cases. Camera A mode is still automatic point and shoot... you just set the fstop first.

Or camera M mode (a TTL mode flash is still automatic flash exposure in camera M mode).


Then (in camera A, S, P, or M mode), if the door is open, the flash will fire.
Open its door manually when you want it, and close it when you don't.
 
Last edited:

algmiyazaki

Senior Member
I think "get it to fire" means "to pop open automatically and then fire". I think you must be using Auto camera mode. In camera Auto mode, the camera system decides (depending on ambient light) when it needs to pop open and fire.

I never use auto, I've been doing all of this in manual mode.

If you instead use one of camera modes A, S, P, or M, then the internal flash will always fire if you open its door manually, and it will never open automatically if you close its door. But Auto mode means that it decides.

I would suggest camera A mode to start. Or camera M mode (a TTL mode flash is still automatic flash exposure in camera M mode).
Then (in camera A, S, P, or M mode), if the door is open, the flash will fire.

This just isn't true with my D5100. When my flash is open in manual mode it doesn't always fire. It will be firing fine and then when I changed my perspective slightly it will stop firing completely (even when it's open). I don't know if my camera is bugged or what. I've searched all over the internet and posted on several forums and no one seems to have an answer. I've never had this problem indoors, only outdoors. It's refusing to fire in certain conditions and I've found no way to override this no matter what I try.
 
Top